About Units

Horsepower: Horsepower (HP) is a unit of measurement of power, originally defined as 550 foot-pounds per second. It is commonly used to measure the power output of engines. For example, the engine of a car might be rated at 300 horsepower. There are different standards for horsepower, including mechanical horsepower, metric horsepower, and electrical horsepower.

Tons of refrigeration: A ton of refrigeration (RT) is a unit of power used to describe the heat-extraction capacity of air conditioning and refrigeration equipment. One ton of refrigeration is equal to the rate of heat transfer needed to freeze 1 ton (2000 pounds) of water at 0°C in 24 hours, equivalent to 12,000 BTU per hour or approximately 3.517 kilowatts.